HSPCs were isolated and transduced with the respective plasmid, then sorted. After 7-9 days in culture ChIP was performed. Briefly, samples were crosslinked, lysed, sonicated and immunoprecipated with the indicated antibody overnight. After a series of washes they were reverse crosslinked overnight and DNA extracted. Library prep was performed at Genewiz, Illumina HiSeq, 2x150bp paired-end reads, multiplexed